Process of making wool-like cellulosic textile materials



PROCESS OF MAKING WOOL-LIKE CELLULOSIC TEXTILE MATERIALS Hugh C. Gulledge, Newark, Del., assignor to E. I. do

' Pont de Nemours and Company, Wilmington, Del., a

corporation of Delaware No Drawing. Filed Jan. 9, 1958, Ser. No. 707,870

9 Claims. (Cl. 8-117) This invention relates to the production of novel, cellulosic materials exhibiting modified properties, .and more particularly to the preparation of improved fibrous cellulosic materials adapted for use in the textile industry.

This application is a continuation-in-art of my copending application, S.-N. 474,587, filed December 10, 1954, now abandoned, which application is a continuation-in-part of my abandoned applications S.N. 370,869 and SN. 370,870, filed July 28, 1953, said applications S.N. 370,869 and 370,870 are continuations-in-part of my abandoned applications S.N. 287,041 and SN. 287,

042, respectively, both filed May 9, 1952. Applications S.N. 287,041 and 287,042 are, in turn, continuations-inpart of my abandoned parent application S.N. 217,407, filed March 24, 1951.

Differences in the properties of. wool and cotton fibers and textiles are well known in the trade and it is'well recognized that a fiber possessing the properties of cotton together with the crease resistance of wool would provide a valuable product adaptable to wide andextensive usage. For instance, such material could be advantageously employed in mens light-weight suitsfor summer wear while presenting an appearance comparable to the warmer woolens, and in the manufacture of womens clothes since a dressy appearance would be desirably assured for substantial periods in warm and humid weather. Although heretofore many treatments have been devised and proposed, the impartation of satisfactory crease-resistance properties to cotton fabrics while retaining other desired and essential features of the fabric has not been successfully accomplished.

Cotton and artificial cellullose derived fibers are deficient in a number of desirable properties, including wrinkle resistance, mildew resistance, abrasion resistance, non-flammability, etc. These Weaknesses are probably greatest in artificial fibers, especially regenerated cellulose type rayon. Heretofore, they have been considered to be a property fundamental to the characteristics of the textile material and not subject to change or modification even after recourse to'relatively expensive treatments. More recently, as contemplated in US. Patent 2,570,566, it has been found that the flame resistance of these textile materials can be remarkably improved by treatment with a strong solution of inorganic chlorides of titanium and antimony. Such treatment yields a cellulosic textile containing both titanium and antimony which is flame resistant.

Signaigo US. Patent 2,525,049 discloses that substantial amounts of titanium oxide can be incorporated in gel cellulosic film by immersing the film in an aqueous solution of a titanium salt. The dried film is brittle and transparent and has properties which are attributed to the presence of the titanium such as the decreased transmission of ultraviolet light. Similar treatment of rayon has not yielded commercially useful fibers and fabrics and such products are not available to the textile manufacturer.

The present invention has among its objects the proice duction of novel, highly useful cellulosic textile materials advantageously possessing wool-resembling properties; to provide new, improved textile materials inherently possessing a novelcombination of desirable properties not heretofore existing in or possessed by any one textile substance, including increased liveliness, mildew resistance, crease resistance, abrasion resistance, flame resistance, greater warmth and insulating characteristics, washability and high melting point; to provide novel methods for convertinginexpensive type cellulosic-materials to more useful, improved products, which, among other things, are competitive with wool and such syn:

thetic fibers as nylon polyamide-condensation-polymer and Orlon acrylonitrile-addition-polymer; to provide a novel,improved form of cellulose textile which 'upon treatment in accordance with the invention contains a treatingmetal in chemical combination with the cellulose; and to provide a novel, reactive cellulose interme-' diate suitable for the preparation of such improved, modi-i fied cellulosic materialstherefrom. Further objects and advantages of the invention will be apparent from the ensuing description thereof.

The above and other objects and advantages are attained in this invention which comprises treating a cellulosic material with a swelling and conditioning agent, reacting the swollen cellulosic product with a metal ester in a substantially non-aqueous environment and preferably in the presence of said agent, regenerating the cellulose product by treatment with aqueous media, and separating and recovering the improved, chemically modi fied cellulosic material fromthe residual organic reagents, solvents and reaction products.

In preparing a modified cellulosic product in accordance with one specific embodiment of my invention, I wet a suitable cellulosic material, such as cotton or rayon, in a substantially anhydrous organic swelling and complexing agent for cellulose, such as an amine, e.g., ethyl amine or ethylene diamine, maintaining a liquid phase, in thereactor. Upon desired preswelling, conditioning or complexing being attained, excess swelling agent is drained or otherwise removed from the swollen and complexd amine cellulose product and the latter is then immersed in a solution of an anhydrous organic metal ester, e.g., alkyl or aryl metal esters of the ortho type, until the metal becomes transferred from the solution to the cellulose by chemical reaction to form a highly tendered metal ester-amine cellulose intermediate compound. This product is then separated from the organic liquid, treated with water or other aqueous media, such as water-com taining organic solvents, e.g., water and alcohol solutions, or dilute aqueous media, and recovery is effected of the resulting chemically modified material as an improved product of greater usefulness.

Complexing agents especially useful in my invention comprise any nitrogenous swelling agent such as ammonia and amine-nitrogen compounds containing a NH or NH radical. Examples thereof include short chain or small ring primary or secondary monoor poly-organic ammonia derivatives. Liquid anhydrous NH ethyl amine, methyl amine, ethylene diamine, and diethylene. triamine are especially useful and effective. Other useful agents includehydrazine, forrnamide, urea, phenyl urea, thio urea, isopropyl amine, propylene diamine, triethylene tetraimine, trimethylene tetramine, dimethyl amine, N-acetyl methylam-ine, diethyl amine, difunctional short chain amine derivatives such as ethanolamine, 1,3-diaminopropanol-Z, aminoethyl ethanolamine, etc. These reactive nitrogenous reagents, known for their ability to swell cellulose'have, proved efiectively useful and can be used in pure state in my process, being added to and caused to react with substantially anhydrous celluluose under pressure and temperature conditions consistent with plexing agent in the liquid state. By conditioning agents I refer to those compounds, usually swelling agents, which suitably modify the cellulose and enable or promote reac-. tion therewith of a titanium or other contemplated metal ester. Since my process is less complicated when the reagent is employed in pure, liquid state, e.g., pure methyl amine or pure ethylene diamine, I preferably resort to such form of reagent. If desired, substantially non-aqueous solutions of the reagent in compatible organic solvents can be employed. The pre-conditioned cellulose reacts with the ester to form a highly tendered ester-amine complex cellulose intermediate which is characterized by a lack of strength prior to the contemplated water or other aqueous media treatment. The process can be carried out by first wetting or immersing the cellulosic material in the desired conditioning agent to induce the swelling, and when desired preswelling and complexing is attained, excess agent is drained from the treated cellulose. The substantially anhydrous metal ester is then added to the cellulose while the latter is still wetted by the amine coriditioning agent, the metallation being preferably effected in the presence of the amine. Preferably also, and to obtain optimum benefits hereunder, the cellulose is in substantially dry state prior to treatment. Under these conditions the improved properties of the final product and beneficial effects of my invention are made possible.

' The metal ester can be added as a pure liquid, or more suitably, as a solution in an organic solvent, such as alcohol, benzene, toluene, xylene, cyclohexane, dioxane, paraffin, hydrocarbon, etc. While tetraisopropyl titanate as a solution in isopropanol is preferred for use because it is one of the less expensive useful titanates from which economical recovery of the isopropanol can be effected, the invention is not limited thereto.

. In general, I contemplate use in the invention of any hydrolyzable organic metal ester or condensed ester or mixture which is adapted to tenderize swollen cellulose.

Those particularly useful are metal esters of the ortho' type corresponding to the formula Me(OR) wherein Me includes titanium, zirconium, hafnium, thorium, aluminum, iron (ferric), etc., e.g., metals which form water insoluble oxides and have a coordination number at least one greater than the valence of the metal in the oxide form (which number is usually 6), R is a monovalent hydrocarbon or chlorinated hydrocarbon radical, such as an alkyl (methyl, ethyl, propyl, butyl, amyl, isopropyl, isobutyl, isoamyl, etc.), cycloalkyl (cyclopropyl, cyclobumyl, cyclopentyl, etc.), aryl (phenyl, naphthyl, etc.), alkaryl (tolyl, xylyl, ethylphenyl, propylphenyl, etc.), aralkyl (benzyl, phenylethyl, phenylpropyl, etc.), and x is 3 and 4, the valence of the metal in its highest state of oxidation. Especially useful are compounds containing an alkyl hydrocarbon radical of an alcohol having from,

say, 1-12 carbon atoms in its chain, and particularly from 1-6 carbon atoms (methyl, ethyl, propyl, butyl, pentyl and hexyl). Other monohydric alcohol compounds of the contemplated metals can be used, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, amyl, octyl, dodecyl titanates, aluminates, zirconates, etc., as well as Z-ethylhexyl, benzyl, cyclohexyl, phenyl, ethoxyethyl and beta-naphthyl derivatives thereof, etc., or various combinations and mixtures thereof. are organic esters or mixtures of an ester of a metal from the first sub-group. of group IV of the periodic table (including titanium, zirconium, hafnium and thorium) or condensed derivatives thereof. Examples of variously useful esters include titanium and zirconium tetraethy'lates, tetraisopropylates, tetrabutylates, etc., aluminum triethylate or tributylate, ferric triethylate, zirconium tetradecylate, etc., and the various hexylates, eth'oxyethylates, cyclohexylates, phenylates, benzylates, and beta-naphthylates of the mentioned metals as well as the monochloro and dichloro, etc., derivatives of these compounds.

The ester-arnine-cellulose intermediate derived from the Especially useful preferred treatment under this invention is severely tendered compared to the cellulose compound resulting from the intial swelling and complexing treatment, or compared to the initial cellulose material. That is, the tensile and tear strength of the fabric is substantially reduced, i.e., by about 10-90% and usually by 10-30% of its original strength, and the tenacity of yarns or fibers is reduced to a similar extent. Upon completion of the reaction, unreacted ester, amine and any solvents used are drained from the intermediate with substantially anhydrous conditions still prevailing. Removal of these unreacted materials can be further facilitated by subsequent displacement washes, using anhydrous organic solvents, followed by draining or other physical separation methods. The anhydrous solvent-Washed ester-amine-complexed cellulose intermediate is useful in various applications. Thus, it can be immediately placed in an aqueous medium, whereupon the hydrolysis product of the intermediate is removed to leave the metal radical in reacted condition within the cellulose structure as a cellulose derivative having substantially the strength and washability and high melting point of the original fibrous cellulose material, but possessing, advantageously such novel properties as high flame and mildew resistance, together with many of the desired single fiber and fabric characteristics of wool, including increased liveliness, greater bulk, warmth and insulating characteristics, initial modulus, compliance ratio, work recovery, crimp elongation, and wool-like woven cloth properties such as handle and high crease resistance. In addition, it exhibits high laundering resistance characteristics, which property and new chemical composition is retained even after repeated washing treatments, as shown in Table 1 below., The intermediate can be held in the anhydrous state for prolonged periods of time before conversion to the improved cellulose derivative form, and hence can be shipped as such, for conversion at other locations or for other purposes.

To a clearer understanding of the invention, the following specific examples are given. These are merely illustrative and are not to be regarded as limiting the invention:

EXAMPLE I 'Viscose rayon twill shirting fabric, after being soaked for 16 hours at room temperature in anhydrous ethylene diamine in a closed container, was removed from the diamine swelling agent, drained and then immersed in a 10% solution of tetraisopropyltitanate in anhydrous isopropanol and heatedto and maintained at or near boiling temperature for two hours while being protected from moisture. The amount of titanate solution reagent used was equal to 25 parts by weight for each part by weight of the fabric. The solution was then drained from the fabric and the latter twice washed with a similar amount of pure isopropanol, each wash involving 30-minute agitation period. As a result, the sample became tenderized to less than a quarter of its original break strength. Unused reagents were recovered from this washing step. The reacted portion of the titanate does not wash out. The sample was then placed in water at 30 C. for 2 hours and then dried, at which point it appeared to be regenerated and had a break strength nearly equal to the original. The- EXAMPLE II A six-ounce desized and washed cotton herring-bone twill fabric after careful drying was soaked in anhydrous ethylene-diamine for 16 hours at room temperature and drained. The material, while wet with the diamine swell- After ten ing reagent, was placed in a 10% solution of tetraisopropyl titanate in anhydrous ethanol, the amount of the solution being 57 times the weight of the dry fabric. The ethanol solution, having the fabric immersed therein was heated to the boiling point and so maintained for 2 hours with suitable precautions being taken to avoid ingress of moisture. The solution was then drained from the fabric and twice washed with similar amounts of absolute alcohol at room temperature. 'As in Example I, this fabric was very tender at this stage of the process. It was then immersed in water where it remained overnight, was drained and dried 3 hours at 110, C. It was then washed with a commercial synthetic detergent solution as in the preceding example and dried. This treated sample regained all its original strength and exhibited new andvaluable properties as shown in Table 1 below.

EXAMPLE III Two ten-gram samples of the 6-02. herring-bonetwill as used and conditioned in Example II were placed in anhydrous ethylamine at C. for two hours and then drained. The swollen samples were each placed in 500 gm. of a solution of tetraisopropyl titanate in isopropanol. Sample A was refluxed 3 hours. Sample B was heated 30 minutes in a pressure vessel at lbs. gauge pressure. Both samples were then washed twice with 300 ml. portions of anhydrous isopropanol as in Example I and then, after draining, placed in 100 ml. of water at 30 C. for one hour and then dried at 110 C. for 2 hours. Their properties, given below in Table 1, were determined after washing minutes at 135 F. in 0.1% commercial detergent solution and drying. v 7

EXAMPLE IV A 3.5 gram sample of the herring-bone twill as used in Examples II and III was swollen with anhydrous ethylene-diamine in the manner shown in Example 11 and drained. It wasthen placed in 200 gm. of a 10% solution of tetraisopropyl titanate in iospropanol under 200 lbs. nitrogenpressure and heated for 30 minutes at 150 C. The fabric at this point was too weak to handle with a stirring rod without tearing. After the two 30 minute washes with isopropanol, the sample was placed in 30 C. water for 4 hours. The fabric recovered most of its strength during water regeneration. After drying and washing as in Example 11 the sample Was tested, its properties being given in Table 1 below.

EXAMPLE V A 4 gm. sample of the fabric used in the three preceding examples was swollen in anhydrous ethylenediamine at room temperature for 16 hours and drained. placed in 200 grns. of a 2% solution of tetraisopropyl titanate in isopropanol and refluxed 4 hours and drained. After washing twice with 200 mg. portions of anhydrous isopropanol it Was placed in Water at 65 C. 'for 30 minutes, then washed and dried as in Example II, to provide a product having the properties given below:

Table 1 Examples Properties Type of Fabric Swelling Agent Titanating Agent 0011 Treated Go trol 13. Abrasion resistance:

retention) Treated Untreated Control Solvent n Flame resistance (duration of at r- Control Mildew Resistance (break strength Prior art treated (U.

containing 5.3% 'liO,

After ten washes at boil.

Explanations:

2. ED=ethylenediamine.

EA=ethylarnine.

3. TPT=tetraisopropyl titanate.

6. Boiling wash-40 rnins. at boil with synthetic detergent solution.

8, 9. Break streng h was determined at the various Five values each for warp and fill were averaged and related to the original break strength.

polymer.

steps to follow degradation andregeneration of the 10. Both rayon and cotton materials were completely soluble in Cu amon. soln.

11. Recovery from crease is obtained in accordance with the procedures referred to in Table .2 below by measuring the angle two minutes after creasing. The crease is made in a 1% x 4 cm. test strip folded and placed under a 1 kg. weight for 5 mine. at relative humidity. The control is a sample given parallel treatment H but omitting the titanation step.

12. Flame resistance was measured by holding a match flame to a hanging strip of the fabric for 10 secondsand timing the duration of flame on the fabric after the match was removed. In all cases the after-flame was very small and resulted in no advance of the burned area.

13. Numbers given are number of cycles of a Taber abrasion tester required to produce the first hole in the fabric.

The commercial resin-treated sample was a similar cloth treated with resin to give crease resistance.

14. Mildew resistance was measured in terms of break strength after 14 days exposure to a pure Chaetmoium culture. N V=no visible surface growth. PG=pr0lific growth.

7 EXAMPLE v1 A skein of viscose rayon yarn was placed in a read tor and immersed in anhydrous ethylene diamine and held at 100 C. for 2 hours after which period the excess unreacted liquid amine was allowed to drain off and the yarn was rinsed once with anhydrous ethanol. A 3% solution of zirconium tetraethylate in ethanol was then added to the reactor, in quantity suflicient to completely immerse the drained skein of amine swollen and complexed rayon yarn. After 2 hours at reflux temperature, the liquid unreacted reactants were drained off, and after two displacement washes with anhydrous ethyl alcohol, the rayon intermediate was found to be highly tendered. This tendered rayon 'yarn was soaked in water, then drained and dried. The dried zirconiummodified rayon possessed strength and shape and color of the original fiber. It was found that the modified rayon contained 17% ZrO and the single fiber properties were closely equivalent to wool.

EXAMPLE VII Four pounds of cotton staple was placed in a 6 gallon staple dyeing machine equipped with a reflux condenser and cooling jacket. The cotton staple was redried after insertion on the machine by passing 100 C. dried air through staple for two hours, and subsequently cooled, maintaining a moisture-free atmosphere with dry nitrogen. Holding the temperature of the reactor of 6 C. anhydrous monoethylamine was circulated through the cotton staple, maintaining a level such that the cotton staple was completely immersed in the liquid amine. After a one-hour period of circulation at 6 C., the liquid amine was drained from the system. The reactor was then filled with 3 gallons of a 45%-by-weight solution of titanium tetraisopropy late in isopropanol. The temperature of the reactor was then raised slowly, allowing the excess ethylamine' to distill out through the reflux condenser. In a period of 1 /4 hours the temperature had reached 60 C., and the volume of the ethyl-amine distilled off was replaced by further addition of one gallon more of the 45%-by-weight solution of titanium tetraisopropylate in anhydrous isopropanol. The reactor was then closed completely, and heated to 88 C. for 1 hour maintaining a pressure of 25 pounds per square inch gauge. At the start of this heating period the liquid of the reactor analyzed titanium tetraisopropylate 24%, ethylamine 15% isopropanol 61% by difference. The unreacted liquid reactants were drained off at the end of the heating cycle, and the reactor containing the titanium-ester-ethylamine-cellulose intermediate was washed thoroughly with anhydrous isopropanol. The washed intermediate was then flushed thoroughly with water, the'titanium-modified cotton staple was then removed from the reactor and dried. This modified cotton was spun into yarn subsequently woven into white suiting fabric of superior wool-like quality. After sanforizing the titanium-modified cotton fabric was crease tested withthe values shown in Table No. 2 being obtained. Its single fiber test results are shown in Table No. 3. Further, the finished product had marked advantage over woolens in that it may be dry cleaned or laundered without loss of quality or usefulness.

EXAMPLE VIII 4 grams of dried continuous filament viscose rayon yarn (l50402.55) was added to a laboratory reactor. Anhydrous methylamine was added to the reactor at 8 C. completely immersing the yarn, and held at that temperature for 24 hours, after which period the reactor was drained and a solution of 30 grams of titanium tetraisopropylate in 13 grams of anhydrous methanol and 100 grams of anhydrous isopropanol was added, being the equivalent of a mixture of titanium tetraisopropylate and titanium tetramethylate in isopropanol, due to esterinterchange. This mixture was heated at reflux temin Table 3. PLE IX 5.7 grams of a continuous filament viscose rayon yarn (ISO-404.55) was dried and placed in a laboratory pressure reactor. Liquid anhydrous ammonia was allowed to fill the reactor completely immersing the yarn. The reactor was held at 27 C. for one hour under 200 pounds per square inch pressure. While maintaining this pressure the excess liquid ammonia was drained off and a solution containing 1900 grams of isopropanol, 312 grams of titanium tetraisopropylate, and grams of methanol was added, being equivalent to a mixture of titanium tetraisopropylate and titanium tetramethylate in isopropanol, due to ester interchange. After this solution had been added the pressure was slowly released, and the reaction held at 82 C. under reflux conditions for 3 hours. After this period the reaction mixture was drained from the reactor, the titanium ester-ammoniacellulose intermediate washed with isopropanol, and then added to cold water, and dried. The dried titaniummodified viscose rayon was of high quality and approached the single fiber properties of wool closely as shown on Table 3. EXAMPLE X 5.6 grams of a continuous filament viscose rayon yarn was dried and placed in a laboratory reactor. Suflicient diethylene triamine was allowed to enter the reactor to cover the yarn, and was allowed to stand in contact with the yarn for 18 hours at 29 C., after which period the excess liquid amine was drained from the reactor. 70 cc. of isopropanol were added to rinse the yarn, and then 50 grams of titanium tetraisopropylate in 225 grams of isopropanol was added, and the reactor held at reflux temperature for 24 hours. The unreacted liquid phase was drained off, and the yarn washed by addition of iso propanol. The titanium ester-diethylenediamine-cellulose intermediate was then added to cold water, and subsequently dried. The single fiber tests, Table No. 3, indicated the titanium-modified viscose yarn was similar to wool.

The textile industry to a large extent recognizes three experimentally determined single fiber parameters as characterizing the resilience of clothing fabrics, namely,

.the initial modulus (Mi), the compliance ratio (CR),

and the work recovery at 3% elongation (3% WR). The resilience parameters of various textile fibers are com-pared in Table No. 3 below with average values of modified cotton and rayon products from Examples VII-X, inclusive, of this invention, and were determined by a conventional Instron type tester procedure (Textile Research Journal, vol. 20, p. 441 (1950)).

Table 2 FABRIC PROPERTY TESTS Made using 1000 gm. wgt. over 5 min. period in accordance with methods and apparatus referred to in article Crease-Resistance and Cotton, by George S. Buck, Jr. and Frank A. McOord, Textile Research Journal, pp. 20-21, vol. XIX, N o. 4, April, 1949.

2 Test described by R. M. Hoffman and L. F. Bests, Textile Research J 21, 66-77 (1951), N o. 2.

I Table 3 SINGLE FIBER TESTS Fiber Test Data 1 Worlr Recovery Exam le Percent p T10; Per- At at 3% at 5% Mi Cr cent E Break, Elong Elong, G. D Percent Percent VII 24 ll 0. 40 24 l. 3 37 27 VIII 22. 5 30 l. 87 47 0. 75 43 24 IX 12 48 0. 76 18 1. 33 22 X 18 41 1.19 31 1. 1 21 Untreated Wool62-64 23 1. 40 1. 3 52 33 Untreated Viscose (150-40- 2.55) 82 .54 12 1.5 13 Untreated Cotton 3O 03 11 2. 3 26 1 Tests conducted in accordance with procedures described by L. F. Beste, et al. article Quantitative Study of Resilience, p. 441, Textile Research Journal, vol. 20 (1950).

EXAMPLE XI A skein of cotton yarn was placed in a reactor and immersed in anhydrous ethyl amine, and held at 8 C. for 2 hours after which period the excess liquid amine was allowed to drain ofi. A 5% solution of ferric triethylate in 1:4 mixture of toluene-ethyl alcohol was added to the reactor containing the drained skein of yarn out of contact with air or moisture in quantity sufficient to completely immerse the amine-swollen and complexed cotton. After 2 hours at reflux temperature, the reactor was drained and after two anhydrous displacement washes with. ethyl alcohol, the cotton was found to be highly tendered. The skein of cotton intermediate was then rinsed with water, and then dried. The dried modified cotton was found to have resumed its original physical shape and strength and was deeply colored brown due to its content of 21.6% iron oxide. Single fiber properties tests showed it to be closely equivalent to wool.

EXAMPLE XII A skein of viscose rayon yarn was placed in a reactor and immersed in methyl amine, and held at 7 C. for 2 hours, after which period the excess liquid was allowed to drain ofi. A 5% solution of ferric ethylate in anhydrous ethyl alcohol was added and the reaction carried out in the same manner as above in Example XII. The iron-modifiedrayon product contained 29.2% iron oxide and was similar in physical and other properties to the product of Example XI, though of somewhat deeper brown color.

EXAMPLE XIII A skein of viscose rayon yarn was placed in a reactor and immersed in anhydrous methyl amine and held at --7 C. for 2 hours after which period the excess unreacted liquid amine was allowed to drain oil. A 5% solution of aluminum triethylate in anhydrous ethyl alcohol was then added to the reactor, in quantity suflicient to completely immerse the amine swollen and complexed rayon yarn. After 2 hours at reflux temperature the liquid unreacted reactants were drained OE, and after two displacement washes with anhydrous ethyl alcohol the rayon was found to be highly tendered. This tendered rayon yarn was placed in water and subsequently dried. The dried aluminum-modified rayon possessed the shape, strength and color of the original rayon yarn. The modified rayon contained 13.0% A1 0 and had single fiber properties very similar to those of wool.

EXAMPLE XIV Five lbs. of viscose rayon yarn (35/2 ply) in lb. skeins was placed in a 6-gallon skein dyeing machine equipped with a reflux condenser and cooling jacket. The

viscose yarn was redried after insertion in the machine by passing 100C. dried air through the yarn for two hours, and subsequently cooled, maintaining a moisturefree atmosphere with dry nitrogen. Holding the temperature of the reactor at 8 C. anhydrous monomethylamine was circulated throughthe yarn, maintaining a level such that the yarn was completely immersed in the liquid amine. After a 5 hour period of circulation at 8 C., the liquid amine was drained from the system. The reactor was then filled with 3 gallons of a 40%-by-weight solution of titanium tetraisopropylate in isopropanol. The temperature of the reactor was then raised slowly, allowing the excess methylamine to distill out through the reflux condenser. In a period of 1% hours the temperature had reached 70 C. and the volume of'the methyl amine distilled oil was replaced by further addition of 2 gallons more of the 40%-by-weight solution of titanium tetraisopropylate in anhydrous isopropanol. The reactor was then closed completely, and heatedrto 86 C. for 4 hours maintaining a pressure of 25 lbs. per square inch gauge. At the start of this heating period the liquid of the reactor analyzed titanium tetraisopropylate 28%, methyl amine 13%, isopropanol 59% by difference. The unreacted liquid reactants were drained oif at the end of the heating cycle, and the reactor containing the titanium-ester-methyl amine cellulose intermediate was washed thoroughly with anhydrous isopropanol. The washed intermediate was then flushed thoroughly with water. The titanium-modified viscose yarn was then removed from the reactor and dried. This modified viscose yarn was woven into an 8 oz. twill suiting fabric of superior wool-like quality. The wrinkle recovery or resistance values obtained are shown in Table 4 below. EXAMPLE XV Employing the equipment of Example XIV, that example was substantially duplicated, except that in lieu of the viscose yarn and swelling agent therein used, there was treated 7 pounds of linen (50/1) yarn in 4 lb. skeins and monoethylamine was employed as the swelling agent. The distillation step was effected over a period of 1 hour at 60 C., while the final heating, with the condensers closed, was over an hour period at C. and under a 25# pressure. The titanium-modified linen product was woven into a summer-weight suiting fabric of superior, wool-like quality, having the values shown in Table 4 below.

- EXAMPLE XVI The procedures of Example XV were duplicated except that in lieu of the linen therein treated 7 pounds of ramie (112/2 linen count) yarn was used. The titaniummodified product yarn was woven into a high quality,

wool-like summer-weight fabric exhibiting the properties thickness. The two layers are wound at right angles to shown in Table 4 below. each other. The thickness of these four layers is then Table 4 FABRIC TESTS Wrinkle Recovery 1 Fabric Analysis Liveliucss I Example Fabric after 1 65% RH, 65% RH, 88% RH} Wash, T cm./sec. Percent Percent Percent Recovery Recovery aiterfimin. afterfimin.

{Titanated Viscose 28. 7 73 71 XIV Untreated Viscose Control 01 64 {'litanated Linen 24 117 87 87 Xv Untreated Linen Control 53 Titanated Ramie 24 218 76 78 XVI Untreated Ramie Control 5O Untreated Wool C0ntr0l 70 88 85 1 Test described by R. M. Hoffman and L. F. Beste, Textile Research I. 21, 66 77 (1951), No. 2. 2 These values were determined in accordance with the wrinkle recovery testing procedures described in Monsanto Technical Bulletin No. 'I7, December 1, 194.7.

3 Relative humidity.

Among the new and unexpected results achieved in my invention, cellulose, for example, in the form of ordinary cotton and having the properties of ordinary cotton, can be eifectivcly modified to a state where its fiber properties resemble those of wool.

In addition, the products of this invention advantageously will retain substantially the macroscopic shape and geometric character of the original cellulose fiber, will be crease and wrinkle resistant and will exhibit other wool-like characteristics, as shown in the above tables. In respect to wrinkle resistance properties alone they will exhibit an at-least-% and usually a or. greater improvement over untreated cotton. Prior art products give very low wrinkle resistance as measured by hand test or by the crease tester method employed in Table 4 above. Although the fibers resulting from my novel treatment have an increased fiber density value substantially as would be expected due to metallation, the bulking value, i.e., vol/wgt. ratio is uniquely increased. This characteristic along with enhanced elasticity which is indicated by elongation at the break point, demonstrates that woollike properties, in addition to crease resistance, are attained by my process. This is shown by the values given in the following table, wherein the first column shows the actual character of the new yarn, while the second column shows the magnitude of the eifect of the treatment on the bulking value of the cotton content of the yarn.

1 Grain per denier.

The yarns used in this test (conducted at 65% relative humidity) were specified as 24/2 ply. The values given were determined by calculating the volume of a gram of yarn from the diameter of the yarn under a constant compression. This diameter is measured by winding two layers of yarn spaced at 30 turns per inch under a 10 gram tension on a stiit S x 5 inchcard of known determined in a Schiefer Compresometer using 3 inch diameter discs at a pressure of 0.25 pound per square inch. One-fourth of this thickness, corrected for the card thickness, is taken as the yarn diameterfor use in calculating the volume per gram of yarn from the known weight and length of yarn on the card. Also microscopic examination shows some change in appearance, especially in respect to micro-crimp, etc. However, the general structure, as indicated by simple visual, non-microscopic observance, remains substantially the same as that of the starting materials. This increased bulking value of the new product is believed to give rise to the desired woollike characteristics such as crush resistance and thermal insulation, thereby giving garments improved Wearability with respect to appearance and thermal comfort.

In the above examples, I have illustrated the invention as applied to certain specific embodiments, but it obviously is not limited thereto. Thus, while the treatment of woven fabrics, yarns and staple has been undertaken, the invention can be utilized in modifying the properties of non-woven textile materials. It has general application to any hydroxyl-containing derivative of cellulose, including commercial wood pulp, paper, cellulose, cellulose sponge, cupra-ammonium rayon, mercerized cotton, and regenerated viscose in the form of fiber or cloth, etc. For example, cotton or rayon staple may be readily immersed in an organic conditioning agent such as enumerated above, separated from the non-absorbed agent and immersed in an anhydrous liquid metal ester composition wherein, for example, the metal is removed from the solution by reaction with the cellulose and becomes an integral part of the cellulose by direct chemical combination. Thereafter, the product is separated from the organic liquids, washed with water, and dried. During this operation the cellulose, whether it be cotton, a regenerated cellulose rayon, or a hydroxyl-containing derivative of cellulose, becomes modified through such chemical combination by the metal ester to result in a cellulosic material containing from about 2% up to 40% or more of the metal or mixtures of metals, calculated as the oxide. Normally, the products of the invention will analyze from about 535% of metal oxide and preferably will contain" from about 10-30% of metal oxide. The use of elevated or boiling temperatures in the reaction of the metal ester with the cellulose material is referred to-in the examples given above, but such is not considered an essential condition in obtaining the beneficial results of my invention. The reaction can be accomplished at lower temperatures through the employment of longer contact time and may be considered to be at the discretion of the operator. The temperature used in removal of solvents after completion of the reactions is likewise flexible and one can employ any suitable vaporization conditions. The variable reaction times, temperature, pressure of the system when swelling and complexing as'well as when reacting and tenderizing the swollen and complexed product by ester treatment, are dependent upon the character of the initial cellulose material, the physical attributes of the swelling agent and the degree of subsequent metallization or degree of change of physical. and chemical properties desired. Hence, such conditions cannot be specifically set out for all individual cases. Where relatively low-boiling liquids are used, such as anhydrous ammonia or methylamine, either low temperature operation at atmospheric pressure, or higher temperature operation at a pressure sufficient to maintain the major portion of ammonia derivative in the liquid state, is required. Short times of contact in both complexing steps, particularly at sub-zero temperatures, are advantageous and effective. A minimum of about 30 minutes of contact is preferred in the first step, that is, swelling and complexing the cellulose with the ammonia derivative; while a minimum of about 15 minutes is preferred in the second complexing, or tenderizing step, during which addition and reaction is efiected of the ester withthe complexed cellulose. The reaction of the ester-ammonia-derivative-complexed cellulose intermediate with water depends on penetration, a period of about 15 minutes to an hour at room temperature being preferred for use in this step.

As noted above, preferably, use iscontemplated herein of a hydrolyzable organic ester of a Fourth Group metal, especially of titanium or zirconium or mixtures thereof. This includes the ortho esters as well as the partially condensed esters. The Fourth Group metal ortho esters are defined by the formula M(OR) in which M represents titanium, zirconium, hafnium or thorium, and R preferably is an alkyl hydrocarbon or chlorinated hydrocarbon radical. For reasons of economy, esters having the smaller alkyl radicals are preferred for use, such as methyl, ethyl, propyl, isopropyl, butyl. However, any ester of this preferred class containing a hydrocarbon radical having up to and including six carbon atoms will prove very satisfactory for use. Chlorinated hydrocarbon radicals 'in this molecular weight range especially those obtained as titanates by the reaction of titanium tetrachloride upon ethylene oxide and propylene oxide are readily employable. The partially condensed titanates and zirconates,- usually formed by the reaction between water and the ortho esters, e.g., tetraalkyl titanates, are also useful in preparing my metallated cellulose- When ortho or slightly polymerized esters are initially used, it is not necessary to have absolutely dry cellulose or amine swelling agent as starting materials. The presence of say a fraction of a percent of Water in the amine solution merely acts to polymerize a portion of the ortho ester used in the metal treating step. The degree of polymerization'of the esters included in this process is preferably less than that obtained by the interaction of an equimolar'quantity of water.

As has been indicated, it is not necessary that substantially all the amine swelling agent be removed from the cellulose prior to treatment with the metal ester or' esters. As a matter of fact, the presence of some concentration of the amine will be found to advantageously enhance the titanation or metallation of the cellulose. For example, with titanium ester employment, titanation can be carried out with as little as 2 or 3% of the amine present with noticeably effective results. Somewhat highermore than 15% amounts are also satisfactory. However, about a 15% concentration of ethylamine or its equivalent of other amine swelling agents has been found to be most useful to obtain optimum results and such amount is preferred for'use. Also, and if. desired, the metallation can be carried out as a onestep operation by immersing the original dried cellulose material in a solution of the metal ester in the amine.

As already indicated, the invention yields a cellulosic textile material which has crease resistance and resilience approaching that of wool. Upon release after pressing, the fibers and textile will readily spring apart, a characteristic known as recovery. These attributes assure production of a material having desired loft (high bulk or volume for a given weight) properties which aiford ready production of wool-like, open, porous fabrics of high covering power and thick, warm fabrics with a minimum of weight, qualities demanded in all apparel fabrics. Additionally, my modified product exhibits other improved characteristics, e.g., mildew resistance, abra sion resistance, extensibility, elasticity and flame resistance, to afford a unique combination of properties which assure essential texture, warmth, fit, and durability characteristies and thereby enhance its value for acceptance by textile manufacturers .and the garment industry.

During the treatments, the strength of the cellulose material undergoing modification becomes poor and fal? rics such as used in the above examples lose strength to such an extent that they are easily damaged by punctures and tears, It is believed that the cellulose is degenerated under the conditions of the process by a breaking of the cross-linkage of cellulose. The titanium, or other metal, enters into combination with the cellulose and the anhydrous product has poor strength due to this lack of crosslinkage between molecular units of the cellulose fiber. Upon treatment with water, however, there is strong evidence that cross-linkage again takes place and the fabric resumes its original strength. The cross-linkage at this time is believed to be somewhat different and a new chemical bonding takes place through the titanium or othermetal which has entered into the complex structure. The improved properties are believed to be due in largemeasure to this new cross-linkage or bonding both units of the cellulose structure. When the product has received normal washing, it is substantially nitrogenfree indicating a relatively pure metal-modified cellulosic material.

That a chemical reaction and new chemical combination exists in the invention is further evidenced from the results obtained when an alkyl titanate, such as tetraisopropyl titanate (TPT) is reacted with an amine-swollen cellulose and measurement is made of isopropanol liberated, in accordance with the following procedure wherein all processing from the drying to the final product was effected under dry nitrogen to eliminate moisture pick-up:

Loose-weave cotton fabric which had been given a thorough alkaline boil-off, washed and dried was employed in the test. The fabric was cut into 1 cm. square pieces, placed in a 2-liter, 2-neck flask and heated in a circulating oven at 110 C. for 2. hours. It was then cooled under dry nitrogen and on analysis for H O was found to contain 0.5% H 0. 49 grams of this dried material was used in the test.

The flask containing the 49 grams of dried fabric was fitted with a 2 (0.5 1D.) vacuum distilling column and a still head for controlling reflux ratio. 890 grams of monoethyl amine redistilled from calcium hydride drying agent and containing on analysis 0.07% H O, was added to the fabric and was held at reflux temperatures for 1 hour. 300 grams of the amine was removed from the flask by suction through fritted glass immersion filter. There was then added a cyclohexane-tetraisopropyl (TPT) titanating solution. This solution had been previouslyprepared by adding grams of TPT to 1000 grams of cyclohexane. The cyclohexane-isopropanol azeotrope (2 parts of cyclohexane plus 1 part isopropanol) was distilled through a 24" packed vacuum still column 0.5" I.D.' until pure cyclohexane came over to provide a titanating solution consisting of 9.5% TPT. During a period of 6 hours, the flask temperature was raised to 60 C., distilling the liberated amine with a 5:1 reflux-ratio (5. parts refiuxed-1 part removed per unit time). The flask temperature was raised from 60 C. to 80 C. during 9 hours, during which time a' 205 gram fraction of distillate was collected boiling at 60-80 C. The titanating solution was drained from the fabric by suction. Excess TPT was removed from the fabric by refluxing with isopropanol and draining the solvent until the wash solvent contained no TPT (8 rinses). The sample was then soaked in water for 30 minutes and oven dried for 2 hours at 120 C. from which a product weighing 60 grams and analyzing 15.4% TiO was ob tained.

The 205 grams of distillate B.P. 60-80 C., collected as described above, was refractionated using the same distillation apparatus with 10:1 reflux ratio. A 114 gram fraction distilling at 6869 C. was collected. This fraction was the cyclohexane-isopropanol azeotrope which consists of 33 /s% isopropanol=38 grams collected from the reaction.

From water analysis of the reagents used, there was added 0.63 gram H O to the reaction by the amine and 0.245 gram E by the fabric=.875 grams total. This amount of water would liberate 5.8 grams isopropanol from TPT. 38-5.8=32.2 grams isopropanol (.535 mol) liberated by the reaction of TPT with the cellulose. From analysis of the product 0.116 mol of Ti reacted.

From this reaction of tetraisopropyl titanate with amine-swollen cellulose under rigid anhydrous conditions and the obtension of 4 mols of isopropanol per mol of the TPT which reacted with the cellulose, evidence of the existence of a chemical combination with the cellulose is established, since in the absence of water, the only way isopropanol could be liberated from TPT during the treatment would be through reation with an active hydrogen, which in this case could only come from the OH group of the cellulose. The amine present during the treatment forms an addition complex with TPT which is easily broken up on heating under conditions of the treatment to liberate free amine and T PT. Assuming complete reaction of the TPT with all hydroxyl groups of the cellulose, the resulting product would contain 18.5% Ti, equivalent to 30.8% TiO A higher percent of chemically combined Ti would result if a partially polymerized Ti ester were used or it up to 1 mol water per mol of TPT were present during reaction.

Other evidence of the existence of a chemical combination of treating metal with the cellulose resides in the excellent mildew resistance which the metallated, especially the titanated, cellulose exhibits. This result does not occur when recourse is had to precipitation of TiO-,, in a cellulosic fabric from an aqueous solution.

I claim:

1. A method for preparing a cellulose textile material possessing substantially the single fiber, liveliness, crease resistance and bulk characteristics of wool, comprising reacting a cellulose textile material under anhydrous conditions in the presence of a nitrogenous chemical swelling agent for cellulose selected from the group consisting of ammonia and amine compounds which swell the cellulose and form nitrogenous complexes with the cellulose and containing a radical selected from the group consisting of -NH and NH, with a water hydrolyzable organic compound selected from the group consisting of (1) an ester corresponding to the formula Me(OR) wherein Me is a metal selected from the group consisting of titanium, zirconium, hafnium, thorium, aluminum and iron and which forms a water-insoluble oxide and has a valence selected from the group consisting of 3 and 4 and a coordination number in the oxide state at least one greater than the valence, R is selected from the group consisting of hydrocarbon and chlorinated hydrocarbon radicals, and x corresponds to the valence of the metal, and

(2) a condensed ester of said hydrolyzable ester resulting from the reaction of said ester with water,

continuing said reaction until a highly tendered metal esteramine cellulose complex intermediate product is formed of substantially reduced tensile and tear strength over that of the swollen cellulose textile, obtained from said chemical swelling agent treatment contacting said metal ester-amine cellulose complex intermediate product with aqueous media consisting essentially of water which regenerates and restores said product to substantially the tensile strength of the original untreated cellulose textile material, and recovering the resulting chemically modified cellulose product.

2. A method for preparing a cellulose textile material possessing substantially the single fiber, liveliness, crease resistance and bulk characteristics of wool comprising reacting a cellulose textile material under anhydrous conditions in the presence of an alkyl amine chemical swelling agent 'for cellulose which swells the cellulose and forms nitrogenous complexes with cellulose, with a water hydrolyzable organic titanium ester corresponding to the formula Ti(OR) in which R is selected from the group consisting of hydrocarbon and chlorinated hydrocarbon radicals, continuing said reaction until a highly tenderized metal ester-amine cellulose complex intermediate is obtained having a substantially reduced tensile and tear strength compared to the swollen cellulose textile, obtained from said chemical swelling agent treatment subjecting said tenderized metal ester-amine cellulose complex intermediate to contact with aqueous media consisting essentially of water which regenerates and restores said cellulose intermediate to substantially the tensile strength of the original untreated textile material, and recovering the resulting modified product containing in chemical combination with cellulose from about 2% to up to 40% of said metal, calculated as the oxide.

3. A method for preparing a cellulose textile material possessing substantially the single fiber, liveliness, crease resistance and bulk characteristics of wool comprising reacting a cellulose textile material under anhydrous conditions in the presence of an alkyl amine chemical swellingagent for cellulose which swells the cellulose and forms nitrogenous complexes with cellulose, with a water hydrolyzable organic zirconium ester corresponding to the formula Zr(OR) in which R is selected from the group consisting of hydrocarbon and chlorinated hydrocarbon radicals, continuing said reaction until a highly tenderized metal ester-amine cellulose complex intermediate is obtained having a substantially reduced tensile and tear strength compared to the-swollen cellulose textile, obtained from said chemical swelling agent treatment subjecting said tenderized metal ester-amine cellulose complex intermediate to contact with aqueous media consisting essentially of waterwhich regenerates and restores said cellulose intermediate to substantially the tensile strength of the original untreated textile material, and recovering the resulting modified product containing in chemical combination with cellulose from about 2% up to 40% of said metal, calculated as the oxide.

4. A method for preparing a cellulose textile material possessing substantially the single fiber, liveliness, crease resistance and bulk characteristics of wool comprising swelling a cellulose textile material by treatment under anhydrous conditions with an alkyl amine chemical swelling agent for cellulose which swells the cellulose and forms nitrogenous complexes with cellulose, subjecting the resulting amine-treated, swollen and nitrogenous complexed cellulose product to reaction under anhydrous conditions with a water hydrolyzable organic ester corresponding to the formula Me(OR) wherein Me is a metal selected from the group consisting of titanium, zirconium, hafnium, thorium, aluminum and iron and which forms a water-insoluble oxide and has a valence selected from the group consisting of 3 and 4 and a coordination number in the oxide state at least one greater than the valence, R is an alkyl radical, and x corre- Ponds to the valence of the metal, continuing said reaction until a highly tenderized metal ester-amine cellulose complex intermediate is obtained, the tensile and tear strength of which is substantially reduced over that of the originally treated swollen cellulose textile, subjecting said metal ester-amine cellulose complex intermediate product to contact with aqueous media consisting essentially of water which regenerates and restores said cellulose intermediate to substantially the tensile strength of the original untreated cellulose textile, and recovering the resulting modified cellulose product containing in chemical combination with the cellulose from about to 35% of said metal, calculated as the oxide.

5. A method for preparing a cellulose textile material possessing substantially the single fiber, liveliness, crease resistance and bulk characteristics of wool, comprising immersing a cellulose textile material under anhydrous conditions in an alkyl amine chemical swelling agent for cellulose which forms nitrogenous complexes with cellulose until a swollen nitrogenous complexed cellulose product is obtained, removing under anhydrous conditions excess amine reactant from the swollen cellulose product and reacting said product under anhydrous conditions in a solution of a water hydrolyzable organic ester corresponding to the formula Me(OR) wherein Me is a metal selected from the group consisting of titanium, zirconium, hafnium, thorium, aluminum and iron and which forms a water-insoluble oxide and has a valence selected from the group consisting of 3 and 4 and a coordination number in the oxide state at least one greater than the valence, R is an alkyl radical, and x corresponds to the valence of the metal, continuing said reaction until an anhydrous, highly tendered metal esteramine cellulose complex intermediate results having a tensile and tear strength substantially reduced over that of the amine-swollen cellulose textile, removing under anhydrous conditions excess ester reactant from said tenderized complex intermediate and immersing said complex intermediate in aqueous media consisting essentially of water which regenerates and restores the intermediate to substantially the tensile strength of the original untreated cellulose textile, and recovering the resulting modifi ed cellulose product containing, in chemical combinatron with the cellulose, from about 5% to 35% of said metal, calculated as the oxide.

6. A method for preparing a cellulose textile material possessing substantially the single fiber, liveliness, crease resistance and bulk characteristics of wool, comprising immersing a cellulose textile material under anhydrous conditions in an alkyl amine chemical swelling agent for cellulose which swells the cellulose and forms nitrogenous complexes with cellulose until a swollen nitrogenous complexed cellulose product is obtained, removing under anhydrous conditions excess amine reactant from said product and reacting the latter at the boil under anhydrous conditions with a solution of water hydrolyzable titanium tetraisopropylate until a highly tendered metal ester-amine cellulose complex intermediate is obtained having a tensile and tear strength substantially reduced over that of the swollen cellulose textile, removing under anhydrous conditions excess unreacted titanate'reactant from said cellulose complex intermediate and subjecting the latter to contact with water which regenerates and restores said intermediate to substantially the tensile strength of the original untreated cellulose textile material, and thereafter recovering the resulting chemically modified cellulose product.

7. A method for preparing a cellulose textile material possessing substantially the single fiber, liveliness, crease resistance and bulk characteristics of wool, comprising immersing a cellulose textile material under anhydrous conditions in an alkyl amine chemical swelling agent for cellulose which swells the cellulose and forms nitrogenous complexes with cellulose until a swollen nitrogenous complexed cellulose product is obtained, removing under anhydrous conditions excess amine reactant from said prod- 18 not and reacting the latter at the boil under anhydrous conditions with a solution of water hydrolyzable zirconium tetraethylate until a highly tenderized metal ester-amine cellulose complex intermediate is obtained having a tensile and tear strength substantially reduced over that of the swollen cellulose textile, removing excess under anhydrous conditions unreacted zirconium tetraethylate reactant from said cellulose complex intermediate and subjecting the latter to contact with water which regenerates and restores said intermediate to substantially the tensile strength of the original untreaded cellulose textile material, and thereafter recovering the resulting chemically modified cellulose product.

8. A method for preparing a cellulose textile material possessing substantially the single fiber, liveliness, crease resistance and bulk characteristics of wool, comprising immersing a cellulose textile material under anhydrous conditions in an alkyl amine chemical swelling agent for cellulose which swells'the cellulose and forms nitrogenous complexes with cellulose until a swollen nitrogenous complexed cellulose product is obtained, removing under anhydrous conditions excess amine reactant from said product and reacting the latter at the boil under anhydrous conditions with a solution of water hydrolyzable ferric ethylate until a highly tendered metal esteramine cellulose complex intermediate is obtained having a tensile and tear strength substantially reduced over that of the swollen cellulose textile, removing under anhydrous conditions excess unreacted ferric ethylate reactant from said cellulose complex intermediate and subjecting the latter to contact with Water which regenerates and restores said intermediate to substantially the tensile strength of the original untreated cellulose textile material, and thereafter recovering the resulting chemically modified cellulose product.

9. A method for preparing a cellulose textile material possessing substantially the single fiber, liveliness, crease resistance and bulk characteristics of wool, comprising immersing a cellulose textile material under anhydrous conditions in an alkyl amine chemical swelling agent for cellulose which swells the cellulose and forms nitrogenous complexes with cellulose until a swollen nitrogenous complexed cellulose product is obtained, removing under anhydrous conditions excess amine reactant from said product and reacting the latter at the boil under anhydrous conditions with a solution of water hydrolyzable aluminum triethylate unti. a highly tendered metal ester-amine cellulose complex intermediate is obtained having a tensile and tear strength substantially reduced over that of the swollen cellulose textile, removing under anhydrous conditions excess unreacted aluminum ethylate reactant from said cellulose complex intermediate and subjecting the latter to contact with water which regenerates and restores said intermediate to substantially the tensile strength of th! original untreated cellulose textile material, and thereafter recovering the resulting chemically modified cellulose product.

References Cited in the file of this patent UNITED STATES PATENTS 2,009,015 Powers July 23, 1935 2,525,049 Signaigo Oct. 10, 1950 FOREIGN PATENTS 517,464 Great Britain Jan. 31, 1940 OTHER REFERENCES Balthis: Abstract No. 692,385, May 16, 1950.

Speer: Ind. and Eng. Chem, February 1950, pp. 251- 253.

Gulledge: Ind. and Eng. Chem, March 1950, pp. 440-444.

Moncriefi: Textile Oolourist and Finisher, August 1950, pp. 394 and 395.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIQN Patent No. 2,980,490 April 18, 1961 Hugh C. Gulledge It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent. should read as corrected below.

Column 1 6 lines 4 25, and 48 and 49, after "textilefl each occurrence strike out the comma; same column l lines 5, 26 and 49 and 50 after "treatmentfi each occurrence, insert a comma; column 18, line 6 strike out "excess" and insert the same after "conditions" in line 7 same column 18.

Signed and sealed this 12th day of December 1961.

(SEAL) Attest: ERNEST W. SWIDER DAVID L. LADD Attesting Officer Commissioner of Patents USCOMM-DC- 

1. A METHOD FOR PREPARING A CELLULOSE TEXTILE MATERIAL POSSESSING SUBSTANTIALLY THE SINGLE FIBER, LIVELINESS, CREASE RESISTANCE AND BULK CHARACTERISTICS OF WOOL, COMPRISING REACTING A CELLULOSE TEXTILE MATERIAL UNDER ANHYDROUS CONDITIONS IN THE PRESENCE OF A NITROGENEOUS CHEMICAL SWELLING AGENT FOR CELLULOSE SELECTED FROM THE GROUP CONSISTING OF AMMONIA AND AMINE COMPOUNDS WHICH SWELL THE CELLULOSE AND FORM NITROGENEOUS COMPLEXES WITH THE CELLULOSE AND CONTAINING A RADICAL SELECTED FROM THE GROUP CCONSISTING OF -NH2 AND >NH, WITH A WATER HYDROLYZABLE ORGANIC COMPOUND SELECTED FROM THE GROUP CONSISTING OF (1) AN ESTER CORRESPONDING TO THE FORMULA ME(OR), WHEREIN ME IS A METAL SELECTED FROM THE GROUP CONSISTING OF TITANIUM, ZIRCONIUM, HAFNIUM, THORIUM, ALUMINUM AND IRON AND WHICH FORMS A WATER-INSOLUBLE OXIDE AND HAS A VALENCE SELECTED FROM THE GROUP CONSISTING OF 3 AND 4 AND A COORDINATION NUMBER IN THE OXIDE STATE AT LEAST ONE GREATER THAN THE VALENCE, R IS SELECTED FROM THE GROUP CONSISTING OF HYDROCARBON AND CHLORINATED HYDROCARBON RADICALS, AND X CORRESPONDS TO THE VALENCE OF THE METAL, AND (2) A CONDENSED ESTER OF SAID HYDROLYZABLE ESTER RESULTING FROM THE REACTION OF SAID ESTER WITH WATER, CONTINUING SAID REACTION UNTIL A HIGHLY TENDERED METAL ESTERAMINE CELLULOSE COMPLEX INTERMEDIATE PRODUCT IS FORMED OF SUBSTANTIALLY REDUCED TENSILE AND TEAR STRENGTH OVER THAT OF THE SWOLLEN CELLULOSE TEXTILE, OBTAINED FROM SAID CHEMICAL SWELLING AGENT TREATMENT CONTACTING SAID METAL ESTER-AMINE CELLULOSE COMPLEX INTERMEDIATE PRODUCT WITH AQUEOUS MEDIA CONSISTING ESSENTIALLY OF WATER WHICH REGENERATES AND RESTORES SAID PRODUCT TO SUBSTANTIALLY THE TENSILE STRENGTH OF THE ORIGINAL UNTREATED CELLULOSE TEXTILE MATERIAL, AND RECOVERING THE RESULTING CHEMICALLY MODIFIED CELLULOSE PRODUCT. 